Much work on biological control of insects has been done in
North America
Japan
Russia
U.K.
Father of green revolution in India is
Which of the following is not an organo-chlorine
Biological control of pests is
Which of the following plants are used as green manure in crop fields and in sandy soils?
Ratio of $CuS{O_4},Ca{(OH)_2}$ and water in ‘Bordeaux mixture' is